问题

Have you realized the difficulty we have ____ the problem?

A:worked out
B:to work out
C:work out
D:working out

正确答案是：

标签： out , realized , work

同类题型

You will be late ________ you leave immediately.[ ]

Dad, it’s such a long way from our home to Tianyi Square!— You mean it’s _________to take a taxi ?

Yesterday I lost my pencil sharpener. I couldn’t find_______.—Oh, it’s a pity. You’d better buy ________ this afternoon.

Is that your best friend Kitty?— No, it _________ be her. She flew to Singapore yesterday.

What happened __________ you, Mary ? You looked so sad.—I couldn’t find my MP3. It’s a present from my mother.[ ]